Impact of transportation demand management (TDM) elements on managed lanes toll prices.

PDFTech ReportBDV26\uc2\ua0977\uc2\ubf02Travel demand managementManaged lanesVariable tollsSimulationTraffic dataExpress lanesLevel of serviceGeneral purpose lanesRidesharingTraffic flowFloridaFlorida. Dept. of TransportationPessaro, BrianBuddenbrock, PatrickNational Center for Transit Research (U.S.)US Transportation CollectionThis research involved a simulation comparing three days of actual traffic data for the I-95 ExpressLanes and General Purpose Lanes in Miami, Florida to a hypothetical scenario where all transportationdemand management (TDM) activities and toll exemptions were eliminated. The purpose of theresearch was to quantify the extent to which carpooling, vanpooling, and transit usage contribute tobetter traffic flow in the I-95 corridor. The express lane analysis revealed a slight degradation in level ofservice (LOS) and a moderate increase in tolls in the southbound direction (+$0.41). It revealed a slightimprovement in LOS and a slight decrease in tolls in the northbound direction (-$0.19). A phenomenonthat occurred was that a large number of inherently low emission vehicles (ILEVs), which are tollexempt, opted out of the express lanes in the hypothetical scenario. The increase in express lane volumefrom former carpoolers, vanpoolers, and transit riders reverting to single occupant status was oftenoffset by even larger volumes of ILEVs leaving the express lanes. Although the traffic impact to theexpress lanes was mild, the impact to the general purpose lanes was more severe. In the hypotheticalscenario, the general purpose lanes operated at LOS F 22 percent more of time in the southbounddirection and 8 percent more of the time in the northbound direction. Furthermore, the traffic densitiesin the general purpose lanes increased 100 percent of the time in the southbound direction and 94percent of the time in the northbound direction